/**
* author: tuncypasha
* file: b.cpp
* created: 02.02.2026 13:04
* Student of Adicto and Raul2008487
**/
#include <bits/stdc++.h>
#define pasha ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define int long long
#define ff first
#define ss second
#define pb push_back
#define all(v) begin(v), end(v)
using namespace std;
// mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
constexpr int N = 5e5 + 5, K = 26, mod = 1e9 + 7, oo = 1e18;
int a[N], pre[N];
array<int, 2> dp[N];
int st[N * 4];
void update(int v, int tl, int tr, int i, int x)
{
if (tl == tr)
{
st[v] = x;
return;
}
int tm = (tl + tr) >> 1;
if (i <= tm) update(v * 2, tl, tm, i, x);
else update(v * 2 + 1, tm + 1, tr, i, x);
st[v] = min(st[v * 2], st[v * 2 + 1]);
}
int find(int v, int tl, int tr, int x)
{
if (tl == tr) return tl;
int tm = (tl + tr) >> 1;
if (st[v * 2 + 1] <= x)
return find(v * 2 + 1, tm + 1, tr, x);
else if (st[v * 2] <= x)
return find(v * 2, tl, tm, x);
return 0;
}
void _()
{
int n;
cin >> n;
for (int i = 1; i <= n; ++i)
{
cin >> a[i];
pre[i] = pre[i - 1] + a[i];
dp[i][0] = -1;
dp[i][1] = oo;
update(1, 1, n, i, oo);
}
dp[1][0] = 1, dp[1][1] = a[1];
update(1, 1, n, 1, a[1] + pre[1]);
for (int i = 2; i <= n; ++i)
{
int best = find(1, 1, n, pre[i]);
dp[i][1] = min(dp[i][1], pre[i] - pre[best]);
dp[i][0] = dp[best][0] + 1;
update(1, 1, n, i, dp[i][1] + pre[i]);
}
cout << dp[n][0] << '\n';
}
signed main()
{
pasha
int t = 1;
// cin >> t;
for (int cs = 1; cs <= t; ++cs){
_();
// cout << '\n';
}
}
